Where does “plumbogummite” come from?

plumbogummite (English) comes from English plumbo-, from Latin plumbum, from Ancient Greek μόλυβδος, from Proto-Indo-European morkʷ-iyo-.

plumbogummite (English): A trigonal-hexagonal scalenohedral mineral...

Definitions

Step	Language	Word	Meaning
1	English	plumbo-	lead
2	Latin	plumbum	lead; ball of lead; pipe of lead
3	Ancient Greek	μόλυβδος	lead; graphite
4	Proto-Indo-European	morkʷ-iyo-	—

plumbogummite — Etymology, Origin & Word History | Etymology Explorer